Clutch



(No Modl.) I 5 sneets sheeu 1.."

G. L. HART.

CLUTCH.

No. 394.976. Patented Dec. 25,1888,

39 I w v 7 Min/eases: I Inventor:

W M/ZMM- u PHERSP'IMO-LiMnpher. Wuhinglon n. c

(No Model.) 7 57Sheets-Shegt 3.

G.L.HART.

CLUTCH.

No.'394,976.. I Patentd Dec. 25, 1888.

. I fnznfiar; I, 0/

N4 PETERS. Ptmbljlhognpher. Washington. D. C.

(No Model.) 5' Sheets-Sheet 4.

C. L. HART.

. GLUTGH.-

No; 394,976. Patented Dec. 25, 1888.

WITNE E farm INVE'NTOR:

3/ his Attorneys,

wmw r61 N. PEYERS, Molilhognphlr, Waihingiofl. D. C.

(No Model.) 5 Sheets-Sheet 5.

G. L. HART. 4

CLUTCH. I No. 394,976. Patented Dec. 25, 18 88.

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UNTTE STATES PATENT FFICE.

CHARLES Ii. HART, OF BROOKLYN, NE\V YORK, ASSIGHOR TO THE E. IV. BLISS COMPANY, OF SAME PLACE.

CLUTCH.

SPECIFICATION forming part of Letters Patent No. 394,976, dated December 25, 1888.

Application filed February 20, 1888. Serial No. 264,703. (No model.)

To all whom iv may concern.-

Be it known that I, CHARLES L. HART, a resident of Brooklyn, in the county of Kings and State of New York, have invented certain new and useful Improvements in Clutches, of which the following is a specification.

This invention relates to that class of clutches wherein a continuously-revolving driving part is coupled at will to a normally stationary driven part and carries the latter with it for one revolution, or for any number of revolutions, until the clutch is released, whereupon the driven part is stopped, usually at the same point in the revolution at which it stood at starting. Such clutches, which are generally known as onerevolution clutches, are most frequently used in connection with power-presses where a plunger or movable die stands normally at the top of its stroke and is driven down upon the bed or fixed die and lifted again to its normal position whenever the operator manipulates a treadle or operating-lever. In such presses the driving part is usually wheel or pulley to which continuous rotation is imparted by a belt or otherwise, and the driven part is a shaft on which said wheel turns freely, and which shaft is formed with a crank or eccentric for imparting motion to the plunger.

My invention, although designed especially for use in power-presses of this class, is nevertheless adapted to a great variety of other uses in connection with driving-shafts and machinery.

My improved clutch is of that class wherein the driving and driven parts are provided, the one with a ratchet-notch and the other with a driving-pawl, the free end of which is pressed out by a spring into engagement with said notch, so that when the pawl is released the driving part engages the driven part through the medium of the pawl and carries the latter around with it. The pawl is retracted by mechanism operated at will to free the pawl and engage the clutch. According to my invention this mechanism consists of a stationary cam-stop having a cam-face in posit-ion to be encountered by the pawl in its rotation and so shaped as to move the pawl out of engagement with the notch, so that the clutch is disconnected, the stop being mounted in such manner that it may be displaced at will out of the path of the pawl, so that the latter is released and permitted to engage the clutch. The cam-face of the stop is so constructed that if the driven part fails to come immediately to rest upon the disengagement of the clutch its motion will be arrested by the contact of the pawl with a raised portion of the cam-face. The portion of the pawl with which the cam-stop engages projects beyond the plane of the ratchet-notch, or, in other words, beyond the plane of an annular recess in the driving or driven part in which the pawl is housed. In order to prevent the rotation of the driven part more rapidly than the driving part, I provide also another pawl and iiotclnwhich are so arranged relatively as to engage in the opposite rotative direction from that in which the driving-pawl and its notch engage. The notch for this retarding-pawl is arranged in position to be engaged byit when the notch for the driving paWl is engaged, so that the driving and driven parts are connected together through the medium of two pawls working in opposite directions, the one forcing the driven part to turn as fast as the driving part and the other preventing the driven part from turning any faster than the driving part. This retarding-pawl is formed with a laterally-projecting portion, which in the position of rest of the driven part is engaged by a stationary throw-off cam, which holds the pawl retracted in order that it shall not make a clicking noise during the free revolution of the driving part by dropping in and out of the notches therein each revolution.

In the accom ntnying drawings my invention is shown as adapted for use as the driving-clutch of a power-press.

Figure l is a perspective view of a powerpress having my clutch applied thereto. Fig. 2 is a view of the clutch on a larger scale, be-

ing a sectional elevation cut on a line with 5 IOO transverse section cut on the line l l in Fig. 3, and looking toward the press-fra1ne. The driving-wheel is wholly removed in this figure. Fig. 5 is a vertical transverse section cut in the plane of the line 5 5 in 3, and looking away from the press-frame. Fig. 6 is a vertical transverse section out in the plane of the line 6 6 in Fig. 3, and looking away from the press-frame. Fig. 7 is a sectional view answering to Fig. (i, but showing the parts in a slightly different position. Figs. 8 and 9 are perspective views of the driving and retardingpawls removed; and Fig. 10is a vertical section answering to I}, and showing a modified construction. Figs. 2, 3, 6, and 7 show the machine while the driven part or crankshaft is at rest, while Figs. 4: and 5 show the clutch engaged and the driven part or shaft carried to half a revolution from its startingpoint.

Let A designate the frame of the powerpress; B,thedriving-wheel thereof; and C, the crank-shaft,which operates the plunger of the press, and which projects through the hub of the driving-wheel and remains normally stationary while the wheel,whichis continuously driven by a belt, revolves freely upon it.

The wheel or pulley B is the driving part, and the shaft 0 is the driven part. In the side of the hub 13 of the driving-wheel there is formed a circular recess, ll, in the definingwall of which are two diametrically-opposite ratchet-driving notches, I) Z), and also two diametrically-om)osite ratchet'retarding notches, d (l. The shaft 0 is formed within the recess 14: with a collar, 18, and a block, 19, made integral with said collar and projecting to one side of the shaft. The collar may be made integral with the shaft or welded or otherwise secured thereto. A driving pawl, a, and a retarding-pawl, c, are pivoted to the shaft by being formed with cylindrical buttends 22,which enter circular seats or recesses 21 21 in the opposite sides of the block 19, this pivotal connection being so constructed as to leave the pawls free to move out and in at I their outer ends sufficiently far to fully enter and fully pass out of the ratchet-notches. The pawls a and c are pressed outwardly by springs 26 and 27, which are held within housings formed in the collar 18 or extending into the body of the shaft, as shown in Fig. 2. The lateral displacement of the pawls is prevented by pins 25, Fig. 4, which are driven or screwed radially through the block 19, so that 1 they intersect tangentially the sockets 21 21 and enter grooves 12 12, formed in the buttends of the pawls, as shown in Figs. 4, S, and 9, so that while the pawls are free to vibrate they are prevented from slipping out of their pivotal sockets.

The preferred construction of the ratchetnotches Z) (Z is that shown, circular recesses 15 15 being bored out at diametrically-opposite sides of the hub 13 and wear plugs or blocks 16 16 being inserted fast in the recesses. The bearing-faces 17 17 of the plugs 16 are made slightly concave, being circular arcs concentric with the pivotal axes of the pawls a and 0 when the latter are in engagement with the notches l) d, as shown in Figs. l and 5, and the ends of the pawls are also roumlcd in circular arcs from the same axial centers. Es sentially, the wheel 1- need be provided with only one notch I) and one notch d; but preferz't-bly two notches of each kind are provided, as shown, so that the same wear plug 16 serves as the abutment-face for both notches. The number of notches may be still further multiplied, if desired.

NOl'lllttll) the driving-wheel 13 is revolving in the direction of the arrow in the several figures and the shaft (.1 is stationary. .l'ts pawl a and 0 being retracted are drawn inwardly in order that their free ends may not engage with the ratchet-notches. The driving-pawl a is held retracted by a cam-stop, E, which is formed with a cam-face, 36, which is normally arranged in the path of a projectioi'i, 42, formed on the pawl (I. This projection 42 extends outside the recess ll, as shown in Fig. 3, and into the plane of the cam-stop E. The shape of this projection 42 is best shown in (i and S.

In order toprovidc means for engaging the clutch the cam-stop E is made movable at will in order to carry it out of the path of the projection 423, so that the pawl amay be freed and be pressed outwardly by its spring. This movement of the cam-stop may be in any suit able direction in order to carry it away from the projection l2;but it is preferably in a direction away from the wheel B, in which case it must move sul'iicienily far to bring it beyond the end of the projection 42. To accomplish this movement the stop E is preferably made in the form of a hinged leaf standing in a plane normally perpendicular to the axis of rotation and parallel with and close to the inner face of the driving-wheel hub and pivoted on a horizontal axis at its lower side, as shown. In the construction shown the hinged leaf is formed in one piece with its pintle 35, on the projecting end of which is fixed a crank-arm, the crz'lnk-stud of which is jointed to the upper end of a rod, 10, which extends down to the bottom portion of the press, where it is jointed to the usual operating-pedal, 39, which is drawn up by a spring, l1. The tension of this spring holds the hinged leaf or stop E normally in the position shown in full lines in Fig. 3, where it stands in the path of the projection 42. \Vhen the treadle is depressed, the stop E is tilted in the manner shown in. dotted lines in Fig 3, thereby freeing the projection 12 and permitting the pawl a to fly outwardly, so that its free end 23 rides against the outer wall of the recess 14:, as shown in Fig. 7. \Vhen in the rotation of the wheel B the next approaching ratchetrnotch b encounters the pawl, the latter enters this notch and its end abuts against the working-face 17 of the wear-plu g 1(i,whereupon this plug drives the pawl before it and through the medium of the pawl it drives the shaft around with the wheel. If, as is usually the case, the treadle be released before one revolution is completed, the cam-stop E moves back into the path of the projection 42, and at the end of the revolution the proj ection rides upon the cam-face 36 and lifts the pawl out of the notch b, thereby disengaging the clutch. The cam-face 36 is of such contour that the rise from the forward edge (which is first encountered by the projection 42) is at first slight, but toward the rear edge the rise becomes more abrupt, forming a 0011- siderable cam projection, 37. The graduallyrising cam-face 3(3 first acts to lift the pawl with a comparatively slow movement until it is lifted quite free from the notch, whereupon, if the momentum of the shaft be inconsiderable or if the retardation due tothe work it is performing be great, the shaft will instantly come to rest. If, however, the momentumof the shaft tends to carry it beyon (1 its normal position of rest, the projection a2 will be brought against the abrupt rise 37 of the cam-face, which will still further lift the pawl until its inner side is brought into firm abutment with the flat face or shoulder 49 on the collar 18, so that by this abutment the pawl becomes essentially a fixed arm or projection from the shaft, which, tending to rotate concentrically around the axis of the shaft, is resisted by the abrupt cam projection 37 ,whereby the further rotation of the shaft is prevented and the shaft is absolutely stopped at a certain limited point in its rotation.

As the exact position of the cam-face of the stop E must be maintained to insure perfect operation, and as the stop is subjected to considerable strain, it is important to provide the stop with an adjustable and at the same time a firm and unyielding supporting-bearing. The preferred construction for this purpose is that shown, where the pintle 35 is carried in a cylindrieally-grooved bearing in a block, 32, which block is socketed in the lower part of a case, 30, which is bolted to the frame A of the press. The block 32 is mounted to slide vertically in its socket in the case 30, and is adjusted up or down by a screw, 45, and when in the proper position is fastened by bolts 33 33, passing through slots in the block and screwing into the press frame. The case or frame 30 is preferably an annular case inclosing the shaft and having a central opening, Ill, elongated to one side in order that in being passed over the shaft it shall admit the collar 18, block 19, and pawls a and c through this opening.

W hen the clutch is engaged and the driving-pawl becomes seated in the ratchet-notch b, the opposite retarding-notch, (7, is in a position coincident with the free end of the retarding-pawl c and is entered by the latter, as shown in Figs. 4: and 5, so that the shaft is prevented from revolving faster than the driving-wheel, whereby the wheel and shaft are positively connected together in both directions. This is an important provision in power-clutches wherein there is a tendency of the shaft to revolve faster than the drivingwheel by reason of the weight of the plunger, which acts to assist the movement of the shaft during its downstroke.

In order to prevent the clicking noise which would otherwise be occasioned by the free end of the retarding-pawl dropping into the successive ratchet-notches during the rotation of the driving-wheel while the clutch is disconnected, and to avoid the consequent wear of the end of the pawl, I provide a stationary throw-off cam, 4H, which is shown as a block secured to or made integral with the annular case 30. This cam 44, has a cam-face formed to gradually approach the center of rotation and arranged in such position that when the retarding-pawl, in the course of its rotation, nears the end of the revolution alateral projection, 43, formed upon the side of the pawl, shall encounter this inclined camface and in riding over it shall be displaced inwardly by it, whereby the pawl c is retracted out of engagement with the ratchet-notches, as best shown in. Fig. (5. The pawl remains thus retracted as long as the shaft remains at rest. Upon the next engagement of the clutch the first movement of the shaft carries the pawl immediately beyond the abrupt end of the cam-block it, whereupon the pawl is released and its free end moves outwardly into engagement with the notch (.Z.

The cam-block it does not interfere with the driving-pawl a, for the reason that it is arranged in a transverse plane beyond the end of the projection .42, as clearly shown in Fig. 3:3. ()n the other hand, the cam-stop E does not interfere with the retarding-pawl, for

the reason that the projection 43, being made narrower than the projection l2, does not extend far enough radially to touch the camstop E in its revolution.

If it be desired that the shaft shall turn more than one revolution, the operator will hold the treadle depressed, thereby holding the stop E out of the path of the projection 42, so that the driving-pawl in passing the step will not be engaged and retracted thereby. When as many revolutions have been made as are desired, the operator will release the treadle and the shaft will then be stopped at the completion of the revolution then being made. In thus driving the shaft continuously the retarding-pawl is retracted by the cam-block at at each revolution; but as this occurs at the top of the stroke of the plunger, where there is no tendency to drive the shaft faster than the driving-wheel, the momentary release of the retarding-pawl at this point in the revolution is not objectionable.

The foregoing description sets forth the specific construction which I preferto employ in the embodiment of my invention; but it is obvious that the construction might be changed in many ways and the parts might IIO be differently arranged without departing from the essential features of my invention. For example, the pawls, instead of being pivoted to the inner of the two con centric parts and engaging notches in the outer part, might be pivoted to the outer part and engage notches in the inner part; also the pawls, instead of being borne by the driven part,which is normally at rest, might be borne by the driving part, so as to be normally in revolution with it. These modifications of my clutch are embodied in the construction shown in Fig. 10, wherein the pawls a and c are represented as being mounted in recesses formed in the wheel-huh instead of being connected to the shaft, and the notches h and (Z are represented as being formed in the block 19, which is fixed to the shaft. The pawls are formed with toes 42 and 43 respectively, which take the place of the projections -12 and i3 in the construction first described, the toe l2 being narrower than the toe L3, in order that it may freely pass an inclined faced block, 50, which acts to throw the retarding-pawl 0 out of engagement with its notch d. The camstop E is mounted similarly to the construction first described, and its cam-face acts upon the toe at? in passing to throw its free end out and prevent its engagement with the abrupt face 9 of its notch b.

I have shown the pawls as being pressed out by springs; but it will be understood that gravity may be substituted as an equivalent for spring-pressure. This may be done in the case of the pawl which, in the position of rest, is arranged at such point in the revolution that its weight tends to throw it into the notch.

I claim as my invent-ion the following-defined novel features and combinations, substantially as hereinbet'ore specified, namely:

1. The combination, with rotative driving and driven parts, the one formed with a ratchet-notch, of a driving-pawl pivoted to the other part and tending to thrust its free end into said notch, and a cam-stop arranged in position to be encountered by said pawl in its rotation and adapted to retract it from engagement with said notch, whereby the clutch is disengaged, and said stop mounted to be displaced at will from the path of said pawl, whereby the latter may be released and the clutch engaged.

:3. The combination,- with relative driving and driven parts, the one formed with a ratchet-notch, of a driving-pawl pivoted to the other part, a spring tending to thrust the free end of said pawl into said notch, and a camstop having a cam-face in position to be encountered by the pawl in its rotation, and shaped to move the pawl, as the latter rides over it, out of engagement with said notch, whereby the driven part is stopped, and said stop mounted to be displaced at will from the path of said pawl, whereby the latter may be released to engage the clutch.

3. The combination, with rotative driving and driven. parts, the one formed with a ratchet-notch, of a driving-pawl pivoted to the other part, a spring tending to thrust the free end of said pawl into said notch, and a cam-stop having a cam-face in position to be encountered by the pawl in its rotation and shaped to move the pawl, as the latter rides over it, out of ei'igagement with said notch, an d subsequently to resist the further rotative movement of the pawl and thereby stop the driven part, and said stop mounted to be displaced at will from the path of said pawl, whereby the latter may be released to engage the clutch.

4. The combination, with rotative driving and driven parts, the one formed with a ratchetnotch, of a spring-pressed drivingpawl pivoted to the other part and formed with a lateral projection beyond the plane of said notch, and a stationary cam stop arranged in position to be encountered by the lateral project-ion of said pawl in its rotation, and shaped to move the pawl, as said projection rides over its cam-face, out of engagement with said notch.

5. The combination, with rotative driving and driven parts, the one formed with a recess and having a ratchet-notch in the defining-wall of said recess, of a spring-pressed driving pawl arranged within said recess pivoted to the other part and formed with a lateral projection extending outside of said recess, and a stationary cam-stop arranged in position to be encountered by the lateral proj ection of said pawl in its rotation and shaped to move the pawl, as said projection rides over its cam-face, out of engagement with said notch.

6. The combination, with rotative driving and driven parts, the driving part formed with a ratchet-notch and the driven part carrying a spring pressed driving pawl and formed with a shoulder or abutment for limiting the retractile movement of said pawl when disengaged from said notch, of a stationary cam-stop having a cam-face in position to be encountered by the pawl in its rotation and formed with a gradual incline, which is' first encountered by the pawl and is shaped to move the pawl out of engagement with said notch, and an abrupt proj ect-ion which is sub sequently encountered by the pawl, and which, when the pawl is seated against said shoulder o abutment, resists the further rotati ve movement of the pawl and thereby of the driven part.

7. The combination, with rotative driving and driven parts, the one formed with a recess having a ratchet-notch in its definingwall, of a spring-pressed driving-pawl within said recess pivoted to the other part and formed with a lateral projection extending outside of said recess, and a stationary camstop consisting of a plate or leaf arranged in a plane perpendicular to the axis of rotation and formed with a cam-face on one side arranged to be encountered by the lateral pro j ection of said pawl in its rotation, and a bearing frame or support for said camstop adapted to hold the same against the thrust against it of said pawl.

8. The combination, with rotative driving and driven parts, the one formed with a ratchet-notch, of a driving-1' a\vl pivoted to the other part, a spring for pressing out said pawl, a cam-stop arranged in position to be encountered by said pawl in its rotation and adapted to retract it from engagement with said notch, said stop mounted to be displaced at will from the path of said pawl, and a bearing part in which said stop is mounted, constructed to be adjustable in order to bring the cam-stop nearer to or farther from the axis of rotation.

9. The combination, with a rotative driving part formed with a recess open at one side and having a ratchet-notch in the definingwall of said recess, a rotative driven part, and a spring-pressed driving-pawl pivoted to the driven part, arranged to rotate within said recess, and formed with a lateral projection extending out at the open side of said recess, of a stationary cam-stop consisting of a plate or leaf formed with a cam-face on one side arranged to be encountered by the lateral projection of said pawl in its rotation and mount ed on a pivotal axis, whereby it may be vibrated at will to bring its cam-face beyond the end of said lateral projection.

10. The combination, with a normally-stationary driven shaft formed with a projecting boss and a spring-pressed driving-pawl pivoted to said boss, of a normally-revolving driving-wheel mounted 011 said shaft and formed with a recess in one side inclosing said boss and pawl and with a ratchet-notch in the wall of said recess, and astationary cam-stop arranged in position to be encountered by said pawl in its rotation and shaped to move the latter out of engagement with said notch.

11. The combination, with rotative driving and driven parts and a clutch for coupling them together at will, one of said parts formed with a retardingnotch, of a retarding-pawl pivoted to the other part and arranged to enter said notch while the driving-clutch is engaged, and a stationary throw-off cam, arranged to withdraw said pawl from said notch at the part of the revolution at which the driving-clutch is released.

12. The combination, with rotative driving and driven parts, the former formed with a retarding-notch, and a clutch for coupling them together at will, of a retarding-pawl pivoted to the driven part and arranged to enter said notch while the driving-clutch is engaged, and a stationary throw-off cam arranged to retract said pawl from said notch when it reaches its position of rest, whereby the clicking and wear of the retarding-pawl during the free revolution of the driving part are prevented.

13. The combination, with rotative driving and driven parts and a clutch for coupling them together at will, one of said parts formed with a retarding-notch, of a retarding-pawl pivoted to the other part, arranged to enter said notch while the driving-clutch is engaged, and said pawl formed with a lateral projection extending out beyond the plane of said notch, and a stationary throw-off cam arranged in the path of said lateral projection and shaped to move the retarding-pawl as said projection rides over it out of engagement with said notch.

let. The combination, with rotative driving and driven parts formed with ratchet driving and retarding notches, of driving and retarding pawls arranged to enter the respective notches, a cam-stop for disengaging the driving-pawl, and a throw-off cam for disengaging the retarding-pawl, the two arranged in clifferent planes, and a lateral projection on the driving-pawl extending into the plane of said cam-stop, and a lateral projection on the retarding-pawl extending into the plane of said throw-off cam.

15. The combination, with rotative driving and driven parts formed with ratchet driving and retarding notches, of driving and retarding pawls arranged to enter the respective notches, lateral projections on said pawls, and one projection extending farther than the other, and the shorter projection extending farther from the center than the other, and a cam-stop for disengaging the driving-pawl, and a throw-off cam for disengaging the retarding-pawl, the two arranged in different planes of the paths, respectively, of the shorter and longer lateral projections, and the one in the path of the shorter projection being farther from the center than the other, whereby it is not encountered by the longer projection.

16. The combination, with rotative driving and driven parts, one of said parts formed with ratchet driving and retarding notches, of a driving and a retarding pawl pivoted to the other of said parts and arranged with their free ends projecting in opposite rotative directions and arranged to simultaneously engage said notches, and a stop for retracting and releasing the driving-pawl at will to engage the clutch.

17. The combination, with rotative driving and driven parts, the one constructed with a recess, 14, in one side, with a ratchet-notch formed in the defining-wall of said recess, and a socket, 15, beyond said notch, with a wearplug, 16, fixed in said socket and having an abrupt face, 17 arranged to form the bottom of said notch, and with a driving-pawl pivoted to the other part and adapted to engage said notch.

18. The combination, with rotative driving and driven parts, of driving and retarding pawls pivoted to the one part and the other part constructed with corresponding ratchetnotches arranged in pairs, with'a fixed wearplug inserted between them and having abrupt wearing-faces formed on its opposite sides to constitute the bottoms of said notches.

19. The combination, with a driven shaft, a

and having lateral projections, a driving- Wheel turning loosely on Said shaft and termed with a recess in one side inc-losing said pawls, and with ratehet-notehes in the defining-Wall thereof, and a eam-stop t'or disengaging said drivingqjiawl, of. a fixed. frame encircling the Shaft formed with a stationary throw-otli' 0am for disengaging the retarding-paivl, and with an adjustable hearingfor said cam-stop.

("IIARLES Ti. :Il'Alt'l.

\Yitnesses:

A. 11'. 'Fazvennn, F. M. Tinrxv m. 

